Yarn separating means



W. K. WYATT YARN SEPARATING MEANS June 27, 1967 5 Sheets-Sheet 1 FiledJune 17, 1965 A 770/?1VEY5.

W. K. WYATT June 27, 1967 YARN SEPARATING MEANS 5 Sheets-Sheet 2.

Filed June 1'7, 1965 I N VENTOR. l/l/LY/ii Jiifhfyail, 62w 6L0 June 27,1967 w. K. WYATT YARN SEPARATING MEANS 5 Sheets-Sheet 5 Filed June 17,1965 June 1967 w. K. WYATT 3,327,462

YARN SEPARATING MEANS Filed June 17, 1965 5 Sheets-Sheet 4 I N VEN TOR.

mz/iam/mmglam June 27, 1967 w. K. WYATT 3,327,462

YARN SEPARATING MEANS Filed June 17, 1965 5 Sheets-Sheet 5- I NVEN TOR.

v ads A T70/7/YEY5.

United States Patent 3,327,462 YARN SEPARA'HNG MEANS William Kirk Wyatt,Lansdale, Pa, assignor to Turbo Machine Company, Lansdale, Pa, acorporation of Pennsylvania Filed June 17, 1965, Ser. No. 464,797 7Claims. Cl. 5734) This invention relates to means for controlling theseparation of double-end (or multi-end) twisted yarn into divided orseparate ends of yarn.

While the separating device of the present invention has other uses, animportant use is as a component of apparatus used for false-twistingdouble-end thermoplastic yarns, and when used for this purpose, theinvention represents a modification of the separating means shown in US.Patent 3,091,908, issued June 4, 1963, to G. A. Carruthers, and assignedto the assignee of the present application.

In one form of apparatus shown in the drawings of the Carruthers patent,conical withdrawal rolls are driven in timed relation with respect tothe in-feed rolls so that the yarn between the withdrawal rolls andin-feed rolls is maintained under a limited and predeterminable amountof tension. The apparatus is preferably so operated that the peripheralspeeds, at approximately the longitudinal centers, of the conicalwithdrawal rolls are equal to the peripheral speeds of the in-feedrolls, and in operation, the conical withdrawal rolls functionautomatically to compensate for any difference of yarn tension as mayoccur between the two single ends of the double-end yarn and tend tocause the point of separation to be maintained at substantially the samepoint.

While conical roll separating means, such as referred to above, operatevery satisfactorily in false-twisting apparatus, they operate best whenthe yarn is supplied or fed through the apparatus at a ratesubstantially equal to that at which it is taken away. However, they mayalso be used satisfactorily for use in false-twisting apparatus in whichthe yarn is passed through a controlled tension device at the in-feedend and pulled through the falsetwist zone by conical nip rolls locatedat the output end, particularly where a tension-control means isprovided.

The present invention provides a yarn-separating control device whichstabilizes the yarn separation point when a controlled amount of tensionis applied at the infeed end.

It has been found that slight differences in frictional resistance ordrag tend ordinarily to occur, and that these cause one of the singleends of the twisted yarn to be withdrawn more readily than the other.Such variations in drag tend to cause the separation point to wander toone side or the other.

An object of the present invention is to prevent such undesirableoccurrences from happening and to maintain or stabilize the separationpoint at a substantially fixed location irrespective of unavoidablevariations in the frictional resistance offered to the individual singleends of yarn.

The invention will be clear from a consideration of the followingdetailed description of several embodiments selected for illustration inthe drawing in which:

FIG. 1 is a perspective elevational view, partly diagrammatic, showingone specifi form of false-twisting apparatus embodying the presentinvention;

FIG. 2 is an enlarged front elevational view showing the front conicaldrive rollers which pull the yarn, and showing the yarn separatingdevice of the apparatus of FIG. 1;

FIG. 3 is a side elevational view of the separating device, which alsoshows the mounting of the rear conical rollers;

FIG. 4 is a top plan view of the conical rollers appearing in thepreceding figures showing also the mounting of the rear conical rollers;

FIG. 5 is a view in perspective showing a modified form of yarnseparating device embodying features of this invention;

FIG. 6 illustrates in perspective another form of separating deviceaccording to this invention; and

FIG. 7 depicts diagrammatically yet another form of separating deviceembodying features of this invention.

The description which follows is phrased in specific terms in theinterest of clarity. Such specific terms are not intended to limit thescope of the invention in any way but are intended only to describespecifically those forms of the invention that have been selected forillustration in the drawings.

Referring now to the specific form of apparatus of the present inventionshown in FIG. 1, a pair of single ends of yarn 20 and 21 from supplysources 10 and 11 are pretwisted, as by hand, to form the double-endtwisted yarn Y, which is passed through false-twist apparatus shown toinclude a tensioning device 12, a heater unit 13, and a cooling zone 14,which may be ambient air. The twisted double-end yarn Y then passesbetween and under a pair of laterally-spaced fingers 36, 37 which arepart of the separation control device identified comprehensively byreference numeral 30. The individual single ends of yarn and 21 thenseparate and pass outwardly over and about guide spools 74 and 75, whichare also part of the separating device 30. The single ends 20, 21, thenpass down between the nips of oppositely disposed pairs of conical niprollers 16, 18, and 17, 19. The single end of yarn 20 which passesthrough the nip of conical rollers 16, 18, passes through guide eye 46down through reciprocating traversing guide 22 and on to a take-uproller 24. The single end of yarn 21 passes through the nip of conicalrolls 17, 19, through guide eye 47, down through reciprocatingtraversing guide 23, and on to takeup roll 25.

Takeup rolls 24 and 25 are spring biased, by means not shown, and aredriven peripherally by frictional engagement with a drive roller 26which is illustrated as driven by electric motor through belt drives 41and 42.

The front roll 16 and 17 of each pair of conical nip rolls is preferablyprovided with a surface of soft resilient rubber or other materialhaving a high coeflicient of friction. The back conical rolls 18 and 19may preferably have a smooth metal surface. The conical nip rolls 16, 18and 17, 19 function to pull the yarn through the falsetwistingapparatus, against suitable tension supplied by device 12.

So far as the present invention is concerned, the conical nip rolls maybe mounted for rotation and driven by suitable means other than asshown. In the preferred embodiment, the front conical rolls 16, 17 aremounted on a common shaft 48, shown as driven by belt 44 which in turnis driven by motor 40 through belt drives 41 and 43. Thus, in view ofthe common drive source 40, the speed of the conical nip rolls 16 and 17has a relationship to the speed of the drive roll 26 which drives thetake-up rolls 24, 25.

In the illustrated embodiment, the front conical rolls 16, 17 are shownsupported by a hollow rectangular support member which projectshorizontally forwardly from an upright plate 52 mounted on frame member53 of the apparatus. Support member 50 has a circular base 51 which isadjustable angularly relative to plate 52 so that the orientation of theconical nip rolls may be adjusted.

An arm 54 is shown secured to, and extending horizontally forwardlyfrom, the upper edge of the plate 52, and supports a vertically disposedplate 56 upon which is mounted the yarn separation control orstabilization device 30. Plate 56 is provided with a vertical slot 156for adjusting plate 56 vertically, as by means of screw 57.

The separating device 36 includes a disc 53 which is pivotally supportedOn plate 56 as by an integral stud 59 having a spring-loaded wing nut159. An inverted generally V-shaped spring-tensioned wire member 70 hasa circular crotch portion which loops over and around the periphery ofdisc 58 and has a pair of arms 72 and 73 which extend downwardly andoutwardly. At the lower extremity of each of the arms '72, 73 is a guidespool 74 and 75.

The arms 72, 73 are spring-tensioned outwardly, and are provided with arestraining collar 76 which embraces the arms 72 and 73 just below thedisc 58. Collar 76 constrains the arms 72, 73 and maintains fixed (andadjustable) the lateral spacing of the guide spools 74, 75. The spacingbetween spools 74, 75 may be reduced by forcing the collar 76 downwardand by holding the collar at its lowered position, as by the adjustablethreaded stop bolt 176. A horizontally disposed U-shaped bracket 77mounted on plate 56, and adjustable vertically, functions as a limitstop for the arms 72, 73, limiting the extent to which the arms may movein the plane of the arms, i.e., laterally relative to the double-endtwisted yarn Y.

The rear conical rolls 18, 1? may be mounted for rotation and pressedagainst the surface of the front conical rolls by any suitable means.One suitable means is illustrated in FIGURES 1, 2, 3, and 4. As thereshown, the rear conical rollers 18 and 19 are supported by L-shapedbrackets 62 and 63. Bracket 62 is adjustably secured pivotally to thetop surface of the hollow rectangular support member 50, as by screw162, and extends outwardly and downwardly, as best seen in FIGS. 1 and2, while bracket 63 is adjustably pivotally secured to the bottomsurface of support member 50, as by screw 163, and extends outwardly inthe opposite direction and upwardly.

Air cylinders 68 and 69, mounted on circular base 51, are adapted topress the brackets 62 and 63 forwardly, thereby to cause the brackets62, 63 to pivot about their respective pivot points and thereby to urgethe rear conical rolls 18, 19 against the forward conical rolls 16, 17.Piston 66 of air cylinder 68 abuts against a finger 64 which forms anintegral part of bracket 62 and extends downward from the upper legthereof. Piston 67 of cylinder 69 abuts against a finger 65 which is apart of bracket 63 and extends upward from the lower leg thereof.

Tension springs 71 and 71a are connected between upright plate 52 andthe pivotal brackets 62, 63 for pulling the brackets pivotallyrearwardly when the pistons 66 and 67 are retracted, thereby to withdrawthe rear conical rolls 18, 19, from frictional engagement with the frontconical rolls 16, 17.

The operation of the false-twisting apparatus of FIG. 1, and of theyarn-separating device of FIGS. 14 will now be described. Assume thatthe hollow rectangular forwardly-projecting support member 50 has beenproperly oriented by angular adjustment of the base 51, and that thespacing between the guide spools 74, 75 at the extremities of arms 72and 73 has been adjusted so that the single ends of yarn 20 and 21 passthrough the nips of the pairs of conical nip rolls 16, 18 and 17, 19 ata suitable point intermediate the ends of the conical rolls.

The rubber-surfaced front conical rolls 16 and 17, driven bythe electricmotor through belt drives 41, 43 and 44, pull the single ends of yarn 20and 21 downwardly over the guide spools 74, 75 and deliver the singleends through guides 46, 47, and 22, 23, to the take-up rolls 24, 25.

In the false-twisting apparatus herein illustrated, the single ends ofyarn 20 and 21 are assumed to have been pretwisted so that a twistextends from the separation point S upwardly, in FIG. 1, through thecooling and heating zones 14, 13, and through the tension device 12 tothe point of convergence P.

At the separation point S, the yarn passes through and then outwardlyunder a pair of forwardly extending spaced-apart fingers 36, 37. Thesefingers receive and oppose the upward thrust of the yarn and prevent thepoint of separation S from moving upstream, thereby maintaining point Sat a fixed level.

So long as the frictional resistance opposing travel downstream of eachend of yarn is equal, the point of separation S will remain laterallysteady, midway between the guide spools 74, 75, If, however, thefrictional resist ance or drag on one of the yarn ends is greater thanthat on the other, the yarn end suffering the larger drag or resistancewill apply a greater laterally-inward and downward force to one of theguide spools 74, '75 than to the other. The greater force will causewire structure 70 to pivot laterally (relative to the double-end twistedyarn as viewed in FIG. 2) and the nip point at which one end of yarn ispulled through its conical rolls which move closer to the small end ofthe rolls, and the nip point of the other end of yarn will move towardthe larger diameter end of its conical rolls. For example, if at a givenmoment it requires more force to pull the right yarn end 21 than it doesto pull the left yarn end 20, guide spool 75 will be forced to the left,as viewed in FIGS. 1 and 2, and the nip point at which yarn end 21passes through its conical rolls 17, 19 will move toward the small endof these rolls. The inverted V-shaped wire structure 70 will thereuponbe forced pivotally to the left, disc 58 rotating clockwise on its pivotaxis 59. Since the spacing between guide spools 74, 75 is held fixed,the guide spool 74 will move to the left, causing the other yarn end 20to pass through its conical rolls 16, 18 at a nip point closer to thelarge end of the rolls. This increases the pull on yarn end 20 and as aresult an increased force is exerted laterally-inward (to the right) onspool 74 which opposes and tends to limit the movement of the wirestructure 70 to the left.

When the pivotal movement of the structure 70, as above described,carries guide spool 74 to the left a sufficient distance to cause thepull on the left yarn end 20 to exceed that on the right yarn end 21,the structure 70 will begin a return movement to the right, and thismovement to the right continues until the pull on the rig-ht yarn end 21equals that on the left yarn 20. The action takes place quickly andserves quickly to stabilize laterally the point of yarn separation S.

To prevent the wire structure 70 from moving pivotally to such an extentthat the yarn ends 20 or 21 are moved beyond the ends of the conicalrolls, or to othe-r-- wise limit the range of the pivotal movement ofwire structure 70, a limit stop is provided in the form of U-shapedbracket 77 mounted on the plate 56 and adjustable in the verticaldirection in slot 156. If one or the other of the arms 72, 73 contactsone of the forwardly extending arms of bracket 77, further movement inthat direction of the wire structure 70 is prevented.

As a further precaution against the yarn ends 20, 21 being moved beyondthe ends of the conical rolls 1619, as for example in the event ofimproper mechanical adjustments to the yarn separating device, there isprovided, in the apparatus illustrated in the drawing, a pair of mercurylimit switches 80 and 81 mounted at opposing ends of a bracket 82secured to the upper edge of disc 58. The mercury switches 80, 81 areopposin-gly disposed at inclined positions. Thus, when the wirestructure 70 pivots more than a selected distance to the left and disc58 is rotated clockwise more than a predetermined amount, the rightmercury switch 81 becomes closed; whereas when the wire structure 70pivots more than a selected distance to the right, thereby rotating disc58 counter-clockwise more than a predetermined amount, the left mercuryswitch 86 becomes closed. Closing of either of the mercury switchesenergizes the relay 83 (FIG. 1) and causes the switch contact 183 toopen, thereby deenergizing the motor 40 to stop the apparatus.

The advantages and features of the yarn separating device 30 of thepresent invention are by now no doubt understood. The device 30 allowsthe conical rolls 1619 to pull pretwisted double-end yarn from theirindividual sources through the heating and cooling zones 13, 14 (whereinthe false twist is set) against a selected amount of drag or resistanceintroduced by the tension device 12, without allowing the yarn ends torun off one or the other end of the conical nip rolls. The device 30functions to compensate automatically for any differences which may tendto occur in the drag or resistance which opposes travel of the separateyarn ends 20, 21 through the false twisting apparatus. The device 30does this (1) by maintaining the ply separation point S substantiallyfixed in the vertical direction (this is done by the fingers 36, 37) and(2) by introducing a counter force which opposes shifting of the plyseparation point in the lateral direction. As already described, it theresistance or drag on the right yarn end 21 should become greater thanthat on the left yarn end 20, the guide spool 75 will move to the left,as viewed in FIG. 1, thereby causing spool 74 to also move to the left.But movement of spool 74 to the left is opposed by the increased forcerequired to pull yarn end at the faster velocity corresponding to thelarger diameter of the conical rolls 16, 18 at the new nip point. Thus,the yarn separation point S tends to be stabilized laterally by thedevice 30. As added features, the device includes adjustment, stoplimit, and protective features already referred to.

While the yarn separating device illustrated in FIGS. 14 and describedabove represents the presently preferred form, other forms may be used.Two such other forms are illustrated in FIGS. 5 and 6. The formillustrated in FIG. 6 is very similar to that of FIGS. 1-4 and will bedescribed first.

In FIGS. 6, the arms 172, 173 which support the guide spools 74, 75 arehorizontally disposed, rather than vertically disposed as in FIGS. 1-4.The arms 172, 173 are separate, rather than integral, and the spacingbetween the spools 74. 75 is adjustable, as by means of a highfrictionbolt and lock nut assembly 158 which allows lowfriction pivotal movementof the V-struc-ture 172, 173 as a unit about point 158 while maintainingthe selected fixed spacing between spools 74, 75. In other respects, thestructure of FIG. 6 is basically similar to that of FIGS. 1-4. Forexample, the fingers 136, 137 of FIG. 6 correspond to fingers 36, 37 ofFIGS. 1-4. These fingers are fixed in position laterally and maintainthe yarn separation point S at a fixed level vertically.

In FIG. 5, the guide spools are omitted, being replaced by thenon-rotatable fingers 274, 275, but this is a relatively insignificantdifference over the structures of FIGS. l-4 and 6, previously described.The more significant difference in FIG. 5 is that the other pair offingers 236, 237, which control the vertical level at which the yarnseparation take place, are mounted on plate 27 0' for pivotal lateralmovement, rather than being fixed as in the case of FIGS. l-4 and 6. Asshown in FIG. 5, the guide fingers 274, 275, and also the fingers 236,237 are mounted on and project forwardly from the lower edge portion oftriangular plate 270 which is pivotally suspended at its upper corner asby a nut and bolt assembly 258 adjustably supported in the slot of asupport member 256. The single yarn ends 20, 21 are taken from the yarnseparation point S down between fingers 236, 23-7, then laterallyoutward in opposing directions, over and around fingers 274, 275, andthen down to the nips of the conical pull rolls. The stabilizing actionis similar in most respects to that already described in connection withFIGS. 1-4 and 6, but with the arrangement shown in FIG. 5, variation inthe vertical level of the separation point S may occur in the event thelateral pivotal motion of the plate 270 is large.

FIG. 7 depicts graphically yet another arrangement in which thetriangular plate 370, mounted for pivotal movement about pivot point358, is provided with but two fingers 336 and 337. The fingers 336, 337control the vertical level of the yarn separation point S.,They alsoserve the function of fingers 274 and 275 of FIG. 5. However, in thearrangement illustrated in FIG. 7, the conical drive rolls are notmounted on a common shaft, as is preferred, and as is the case in all ofthe previously described embodiments.

The stabilizing action in FIG. 7 is generally similar to that previouslydescribed and will by now be readily understood.

While the drawings show a twisted pair of yarns, it will be appreciatedthat multiple yarns may be processed or that more than one twisted setmay be processed concurrently in a single apparatus. The yarns may varywidely in total denier and in number of filaments.

It will also be appreciated that, while the invention has been describedin detail with reference to specific em bodiments thereof, many changesmay be made without departing from the scope of this invention. Forexample, equivalent elements may be substituted for those shown anddescribed, parts may be reversed, and certain features of the inventionmay be used independently of other features, all without departing fromthe spirit and scope of the invention as defined in the appended claims.

What is claimed is: I

1. In an apparatus for modifying heat-settable yarn filaments whereinsaid yarns are pretwisted and conducted in a tensioned conditionlongitudinally downstream through a heat-setting zone, and whereinwithdrawal means are provided for drawing the heat-set yarns outwardlyapart, said withdrawal means being automatically operative in responseto variations of yarns feed positions to vary withdrawal rates in amanner to equalize the tensions of the yarns withdrawn, the combinationwhich comprises stabilizing means having a pair of laterallyspaced-apart guides arranged at opposite sides outwardly of the yarnpath, each being arranged in guiding relationship with one of theseparated yarns, said guide means being adapted to receive and opposethe downstream and laterally inwardly directed components of thrust ofsaid separate yarns, support means arranged to support said guide meansfor unitary movement laterally back and forth according to the relativemagnitudes of inwardly directed components of thrust, for changing saidfeed positions in response to differences sensed in said relativemagnitudes; upstream-thrust-receiving means between said pair oflaterally spaced-apart guides for preventing the yamseparation pointfrom moving upstream; and stop means for limiting the lateral movementof said guid means.

2. In yarn modifying apparatus; spaced pairs of conical nip rollsthrough the nips of which pass, after separation, the first and secondsingle ends of a doubleend twisted yarn, said conical rolls beingadapted to pull said yarn under tension through a modifying zone indouble-end twisted condition; and means for stabilizang the point atwhich the double-end yarn is separated into said first and second singleends, said stabilizing means including: first and second guide meansspaced apart laterally, one on either side of the path of saiddouble-end yarn, and about which the single ends of yarn arerespectively passed enroute to the nips of the respective pairs ofconical rolls, said first and second guide means being adapted toreceive and oppose the downstream and laterally inward components ofthrust of the said angle ends of yarn; pivotally-mounted support meansfor supporting said first and second guide means for unitary movement inone lateral direction or the other according to the relative magnitudesof the inward components of thrust, for changing the nip points inresponse to diiferences sensed in said relative magnitudes; means fixedmounted between said first and second guide means for receiving andopposing the upstream thrusts of said single. ends of yarn forpreventing said separation point from moving upstream; and stop meansfor limiting thev lateral movement of said first and second guide means.

3. Apparatus as claimed in claim 2 characterized in that a power driveis provided for said conical nip rolls and in that switch means areprovided mounted on said pivotal support means for shutting off thepower drive when the pivotal movement reaches a predetermined limit.

4. In a false twisting apparatus in which left and right pairs ofconical nip rolls are employed beyond the yarn separation point topullseparately the single ends of pretwisted double-end yarn through anin-feed yarn tensioning device and through a false-twisting zone; a yarnseparating device for controlling and stabilizing the point at which thedouble-end yarn separates into the two single ends, said deviceincluding: left and right yarn guides at fixed spacing laterally fromeach other, one on either side of the vertical plane of the double-endtwisted yarn in the false-twist zone, for guiding the separate singleends of yarn to the nips of said left and right pairs of conical rollsrespectively and for receiving. and opposing the laterally inward anddownstream components of thrust of said single ends of yarn; pivotalsupport means supporting said left and right yarn guides for lateralpivotal movement while maintaining their spacing fixed relative to eachother; fixed means disposed between, said left and right yarn guides forreceiving and opposing the upstream components of thrust of said singleends of yarn for preventing movement of the separating point in anupstream direction; andmeans for adjusting the position.

of said fixed means.

5. Apparatus as claimed in claim 4 further. characterized inthat meansare provided for adjusting the fixed spacing between said left and rightyarn guides.

6. Apparatus as claimed. in claim- 5 further characterized in that stopmeans are pivoted for limiting the lateral pivotal movement of said leftand right yarn guides.

7. Apparatus as claimed in claim 6 further characterized in that powerdrive mans are provided for driving said left and right pairs of conicalrolls and in that switch means are provided for disconnecting said powerdrive when the lateral movement of said yarn guides reaches apreselected limit.

References Cited UNITED STATES PATENTS 2,987,869 6/ 1961 Klein 57343,091,908 6/ 1963' Carruthers 57-34 3,192,697 7/ 1 965 Carruthers 57-34'3,237,391 3/ 1966- Carruthers 57-34 X 3,261,116 7/1966 Kunzle et al2-872 X 3,261,155 7/1966 Kunzle' 2872 X 3,261,156 7/1966 Kunzle et al2872 X FRANK J. COHEN, Primary Examiner.

D. E. WATKINS, Assistant Examiner.

1. IN APPARATUS FOR MODIFYING HEAT-SETTABLE YARN FILAMENTS WHEREIN SAIDYARNS ARE PRETWISTED AND CONDUCTED IN A TENSIONED CONDITIONLONGITUDINALLY DOWNSTREAM THROUGH A HEAT-SETTING ZONE, AND WHEREINWITHDRAWAL MEANS ARE PROVIDED FOR DRAWING THE HEAT-SET YARNS OUTWARDLYAPART, SAID WITHDRAWAL MEANS BEING AUTOMATICALLY OPERATIVE IN RESPONSETO VARIATIONS OF YARNS FEED POSITIONS TO VARY WITHDRAWAL RATES IN AMANNER TO EQUALIZE THE TENSIONS OF THE YARNS WITHDRAWN, THE COMBINATIONWHICH COMPRISES STABILIZING MEANS HAVING A PARI OF LATERALLYSPACED-APART GUIDES ARRANGED AT OPPOSITE SIDES OUTWARDLY OF THE YARNPATH, EACH BEING ARRANGED IN GUIDING RELATIONSHIP WITH ONE OF THESEPARATED YARNS, SAID GUIDE MEANS BEING ADAPTED TO RECEIVE AND OPPOSETHE DOWNSTREAM AND LATERALLY INWARDLY DIRECTED COMPONENTS OF THRUST OFSAID SEPARATE YARNS, SUPPORT MEANS ARRANGED TO SUPPORT SAID GUIDE MEANSFOR UNITARY MOVEMENT LATERALLY BACK AND FORTH ACCORDING TO THE RELATIVEMAGNITUDES OF INWARDLY DIRECTED COMPONENTS OF THRUST, FOR CHANGING SAIDFEED POSITIONS IN RESPONSE TO DIFFERENCES SENSED IN SAID RELATIVEMAGNITUDES; UPSTREAM-THRUST-RECEIVING MEANS BETWEEN SAID PAIR OFLATERNALLY SPACED-APART GUIDES FOR PREVENTING THE YARNSEPARATION POINTFROM MOVING UPSTREAM; AND STOP MEANS FOR LIMITING THE LATERAL MOVEMENTOF SAID GUID MEANS.